I need to edit an 85 minute feature movie (shot with the DVX100) on a Powerbook laptop. My question is, can I just hook up a large external Firewire b (800) hard drive to fulfill my needs. I'm new to this DV NLE thing.

Absolutely. That's how many folks on this board do their editing. Even Firewire 400 is plenty fast enough for over the wire DV editing.

5 minutes of DV footage takes up about 1GB of space. I'd think if you just bought the drive you'll have plenty of space and speeed!

FW400 gives problems for some people (dropped frames). Factors:

#1- Other devices on the same firewire bus. Some combinations do not play well.
#2- Speed of the drive (bigger is better), the bridge chipset used (oxford 911 is better AFAIK for FW400)
#3- How full the firewire drive is.
#4- Alignment of the stars and the moon?

FW800 is the same speed as internal drives. I have never heard of anyone having problems with FW800

Well FW800 is pretty new, but for all those years up until now, FW400 has worked beautifully for DV editing - many on this forum will heartily concur, since I know many of us use it. If you do encounter dropped frames and other oddities, either your firewire card is the problem, or your pet cat has chewed through your firewire cord. Either way, those problems would occur in FW800 too.

But yes, a FW800 connection puts you at roughtly the same speed as an internal IDE drive.

Mac's don't have FireWire cards, they are built in and can't be exchanged like PC's. So, FireWire cards are not the issue on Mac's. The original poster is not mentioning FireWire issues, so I'm not sure why they are being brought up. In my extensive experience with Macs, most dropped fame issues are the result of time code problems on the tape, or problems with the FireWire protocol on the playback (capture) device.

Right- the card thing was what I loosely meant as your firewire interface (on most PCs these days there's no separate 'card' either). I'm just used to saying card - old habit. I did think the discussion was pertinent though, since Gipson mentioned he was new to this and the speed down the wire is the most common concern.

A small minority of folks on the lafcpug.org forum report problems with dropped frames with firewire drives. If you search, you will find that certain combinations of deck + FW drive and combinations of many firewire drives do not play well together.

Your mileage will vary with FW400 drives. With FW800, I would feel a lot safer for a few reasons:
A- Drives are faster under the FW800 interface. They are the same speed as if the drive were an internal 7200rpm drive.
B- The FW800 sits on the FW800 bus and does not share it with FW400. This avoids problems with certain FW combinations.

If you search, you will find that certain combinations of deck + FW drive and combinations of many firewire drives do not play well together.
That is exactly what I said, most FireWire issues are the result of the capture devices (certain cameras and decks) not following the FireWire protocol. FireWire 800 has it's own set of issues, but either work fine for the vast majority of G5 users and Mac users in general.

Glenn,
My personal experience using FireWire on my PowerBook G4 has been almost flawless. I just finished editing a 35 minute short film with a new 250 GB WesternDigital FireWire 400 hard drive and FCP4 (it was shot with my VX2000) and i didn't have any problems.

As a precaution I did run the hard drive off of a firewire cardbus and then ran the camera directly from the FW 400 port on the PowerBook as my model doesn't have a FW800 port.

If you can spare the slightly extra expense I'd recommend going with the FireWire 800 drive as the others have mentioned it'll give you a faster transfer rate and having everything on separate buses will help avoid any potential strain on your system.

I'd agree that firewire 400 drives work very well; haven't tried an 800 yet although my new powerbook does support it. I have a total of 7 external firewire drives, bought over the past few years. The only problems were older drives, one of which had a slower chipset (before the Oxford 911 series was available) and the other was cheap 5400 RPM drive which I ended up giving to a friend. I think anyting you find today should serve you well.

Happy editing!